SRDF FA Ports (RFb) % Utilization

Hello.
I'm trying to make a Performance Analisys and when I look into
Performance Manager to get information about the % of
utilization of the main components of a Symmetrix I´m able to
get it, most of them except for RDb ports, wich only gave me
IOS,request, KBS request, read/Writes request and KB
sent/received per sec.

I need to know wich is the maximum capacity of I/O per sec that
an RFb can manage (We have a Symm 8730 and a DMX 1000-M2)? or
know how to create that % utilization metric, if it's possible?

You are asking for something that only people sign NDAs for it can have.

There is no specific I/Os per second as a metric. It varies by request size (an FC constraint) and capability of onboard processors (a hardware constraint). This is true for all FC arrays and is a surprise to most.

In the case of remote links, you would also add latency induced by distance and latency induced by circuitry. In addition, the type of replication would have an impact.

You need to press your vendor for the answer. Your contract with the vendor prevents you from posting the answer.

At the end of the day the FC protocol has no inbuilt way of managing
performance metrics. It is a failing of the FC protocol itself. Those
who remember mainframe will know that performance data collection was
in-built. Those responsible for FC need to get focus and build in a
method for adding performance data to each FC packet as it is generated
and release that as a standard.

If that may help you : we have analyzed many SRDF link
performance (between 8730 or 8830) on distant link or local link
(direct fibre from one Sym to another) and we noticed that we
could never get more than 30 MByte per second of trafic per SRDF
FC link (on dual-port DP3-FCD2 or quad port DP3-FCD42G FC card,
with 1 Gb/s ou 2 Gb/s speed, even when performing full
resynchronization : everytime the limit is the same). So we
guess that is the upper limit for this generation of Sym.

If your reach this limit (or even half of this limit), you should
think about adding one more SRDF FC link between the Syms. If
you are below this limit, you can't know when you reach the
limit of your installation as it depends on the network between
the 2 Syms and the size of blocks you send accross SRDF...

And even below the limit of your installation, you may experience
bad response time as the link charge is growing.

So I think the best practise is to add more SRDF links when you
notice that the response time of your disks is growing too much.
You can compare performance from one year or one month to
another and check if the SRDF volumes response time is growing
almost lineary or exponentialy. If it grows exponentialy, you
should better add SRDF links before it grows too much that means
before end-user experience bad response time from their
application due to bad response time from the Sym.